1. Technical Field
The present invention relates to an electronic timepiece that receives and obtains the current date and time from satellite signals transmitted from positioning information satellites such as GPS satellites.
2. Related Art
Electronic timepieces that receive and acquire the current date and time from satellite signals transmitted from positioning information satellites such as GPS (global positioning system) satellites, and display the reception level are known from the literature. See, for example, Japanese Unexamined Patent Appl. Pub. JP-A-2009-180555.
The electronic timepiece described in JP-A-2009-180555 displays the reception level in three levels, 0, 1, 2. When in the timekeeping mode and the number of GPS satellites that are locked onto is 0, the reception level is 0; when one or more GPS satellites are found but do not include a GPS satellite with an SNR equal to or greater than a specific level, the reception level is 1; and when signals are received from one or more GPS satellites with an SNR equal to or greater than the specific level, the reception level is 2.
In the positioning mode that acquires positioning information, the reception level is 0 if 3 or less GPS satellites are locked onto; the reception level is 1 if the number of GPS satellites locked onto is at least 4 and the number of GPS satellites with an SNR equal to or greater than the specific level is 3 or less; and the reception level is 2 if the electronic timepiece locks onto four or more GPS satellites with an SNR equal to or greater than the specific level.
Even users without a sufficient understanding of how the GPS system works can thus easily determine the reception state because the reception level is displayed in three levels.
Determining the reception state more precisely is difficult, however, because the reception level is displayed in only three levels. For example, when the reception level is 0 in the positioning mode, determining whether three GPS satellites were locked onto, or whether reception is simply not possible in the current location, is not possible.
In addition, when three satellites have been locked onto, the possibility of locking onto a fourth is high, and reception is therefore preferably continued. On the other hand, because the possibility of being able to acquire information is low even if reception continues when even one satellite cannot be received, reception is preferably terminated promptly to reduce power consumption. Because the action to be taken thus preferably differs according to the conditions when the reception level is 0, the ability to know the reception state in greater detail is desirable.